Soil Test Phosphorus in Kentucky Counties with Municipal Separate Storm System Communities.

Kentucky has 104 Municipal Separate Storm Sewer System (MS4) communities in 32 counties where 65% of the population resides.  These MS4 communities are regulated by the Environmental Protection Agency to meet six minimum control measures.  One of the measurable goals outlined by the EPA, to meet the Public Education and Outreach minimum control measure, includes the number of soil test requests within the MS4 communities.  In support of a proposed partnership with the MS4s and the county Cooperative Extension Service offices where the MS4s are located, we summarized 25 years of soil test phosphorus results between 1990 – 2014 and compared the results for samples collected in agronomic fields relative to samples collected in home lawns and gardens.  Soil test phosphorus (Mehlich 3) results have been divided into 4 categories: less than 15 mg kg^-1 (deficient), 15 – 30 mg kg^-1 (adequate), 30 – 60 mg kg^-1 (surplus) and greater than 60 mg kg^-1 (environmental concern).  Within every county soil test phosphorus from home landscape samples exceeded soil test phosphorus from agronomic field samples.  This comparison demonstrates a large educational opportunity in the urban environment regarding responsible nutrient management.